In fog, a pilot vessel is required to sound one long blast followed by two short blasts on its whistle at intervals of not more than two minutes. The long blast indicates the vessel's presence, while the two short blasts signal its role as a pilot vessel. This sound signal helps other vessels in the vicinity to identify the pilot vessel's location and intentions in reduced visibility conditions.
A Fog Horn.
A power-driven vessel under way sounds one prolonged blast not less than every two minutes. However if it is less than 12meters in length it is not required to give any signal.
Rule 35 part c of the International Regulations for Preventing Collisions at Sea (72 COLREGS) states that when in restricted visibility (i.e. fog) a sailing vessel is required to sound one prolonged blast followed by two short blasts on the vessel's whistle, at intervals of not more than two minutes. Please refer to the link below.
The sound signal that you should hear when a power boat is in the fog is one prolonged blast at intervals of no more than 2 minutes.
I am a power-driven vessel underway. Sound signals let other boaters know where you are located during periods of restricted visibility, such as extreme fog. If you hear the fog signal of a vessel you cannot see, slow to a minimum speed until you are sure there is not a risk of collision. One prolonged blast at intervals of not more than two minutes is the signal used by power-driven vessels when underway.
I am a power-driven vessel underway. Sound signals let other boaters know where you are located during periods of restricted visibility, such as extreme fog. If you hear the fog signal of a vessel you cannot see, slow to a minimum speed until you are sure there is not a risk of collision. One prolonged blast at intervals of not more than two minutes is the signal used by power-driven vessels when underway.
One prolonged blast followed two short blasts, every two minutes, not to exceed two minutes. Rule 35-Sound Signals in restricted visibility.
Rules of the RoadRule 35Sound Signals in Restricted Visibility(C) A vessel not under command, a vessel restricted in her ability to maneuver, a vessel constrained by her draft, a sailing vessel, a vessel engaged in fishing, and a vessel engaged in towing or pushing another vessel shall..........sound at intervals of not more than two minutes, three blast in succession, namely one prolonged followed by two short blasts.
A sailing vessel making way should signal, long-short-short every two minutes in fog.
A vessel of more than 100 meters in length that is at anchor must sound a fog signal consisting of one long blast followed by two short blasts at intervals of not more than one minute. This signal alerts nearby vessels of its presence in reduced visibility conditions. The long blast lasts for about four to six seconds, while each short blast lasts for about one second.
A powerboat underway in fog should sound a prolonged blast on its horn at intervals of not more than two minutes. This signal alerts other vessels to its presence in low visibility conditions. Additionally, if the vessel is maneuvering or making way, it may also sound short blasts as required for specific maneuvers. Always be prepared to adjust your signals based on the surrounding conditions and the presence of other vessels.
One prolonged blast plus two short blasts every two minutes. Explanation: Sound signals let other boaters know where you are located during periods of restricted visibility, such as extreme fog. If you hear the fog signal of a vessel you cannot see, slow to a minimum speed until you are sure there is not a risk of collision. One prolonged blast plus two short blasts at intervals of not more than two minutes is the signal used by sailing vessels.